Question

Which of the following is true with respect to sodium thiosulphate?

• A. It gives brown precipitate with mercuric nitrate.
• B. It gives black coloured precipitate with silver nitrate.
• C. It gives white coloured precipitate with lead acetate.
• D. It gives white precipitate with barium chloride solution.

Answer 1

Answer: (C), (D)

It gives white coloured precipitate with lead acetate.
It gives white precipitate with barium chloride solution.

$N{a}_2{S}_2{O}_3+HgN{O}_3⟶H{g}_2{S}_2{O}_3\downarrow +2NaN{O}_3$

$N{a}_2{S}_2{O}_3+(C{H}_{3}COO{)}_{2}Pb⟶2C{H}_{3}COONa+Pb{S}_2{O}_3\downarrow$

$N{a}_2{S}_2{O}_3+BaC{l}_2⟶2NaCl+Ba{S}_2{O}_3\downarrow$

$N{a}_2{S}_2{O}_3=AgN{O}_3⟶A{g}_2{S}_2{O}_3\downarrow +2NaN{O}_3$

Sodium thiosulphate gives white ppt with barium chloride and lead acetete.